Define Energy and Protein requirements in geriatric nutrition?
Decreased physical activity and changes in body composition and decreased basal metabolic rate affects the macronutrient energy, protein requirements. It has been established that 0.8 gm protein /kg body weight/day in universally recommended providing about 15-20 en% (percent of energy). The protein intake may be increased or decreased depending on illness/ convalescence.
The estimated energy requirements decrease by 0.5-1.0 % per year and are based on physical activity level, weight, height and age of the individual - 25-30 Kcal/kg/day (increased in hypermetabolic state). With aging loss of muscle mass and strength (sarcopenia) is observed. It has been seen that decrease in physical activity causes these body composition changes. These processes lead to a lower energy requirement. Due to the decrease in lean tissue, the BMR declines by about 5% per decade. Thus for maintenance of lean body mass, physical activity is most important. It is also important to emphasize the elderly to maintain adequate energy intake to prevent either underweight or overweight. Underweight may be observed in persons who have 'anorexia of aging' and depression. They may have gait instability, falls, and fractures, delayed wound healing etc.